For improving safety and battery property of secondary batteries, there has been proposed a technique of using non-conductive inorganic particles such as alumina particles to form a porous membrane on a surface of an electrode active material layer of an electrode (see Patent Literature 1). However, in the porous membrane using the non-conductive inorganic particles, it is concerned that the battery property may deteriorate due to dissolution of metal. In order to solve this problem, there has been proposed a porous membrane using non-conductive particles formed from a polymer (see Patent Literatures 2 and 3).